This week millions of real votes will be cast in local elections in England that can be compared with real preferences in nationwide opinion polls asking who should govern Britain. Party strategists will examine results for signs of what this means for the general election outcome, even though neither form of evidence is exactly comparable to a general election vote.
This year's local election results will be real but unrepresentative. First of all, the choice of councillors is confined to England. This leaves out parts of the United Kingdom that collectively return 107 Members of Parliament. Secondly, more than half the registered electorate will not turn out to cast a vote. Thirdly, the choice of parties and independents differs from council to council, and is often different from party competition in parliamentary constituencies. Finally, since local issues and personalities differ from national ones the reasons for casting a council vote often differ from voting for a prime minister.
The Conservatives are on the back foot in this year's local elections because they are defending 899 council seats they won in 2021 when the party was ahead in nationwide opinion polls. This is no longer the case. Local election experts Colin Rallings and Michael Thrasher forecast that the Tories are at risk of losing upwards of 55 percent of the council seats they are defending in England.
The Conservative loss of more than half their English council seats implies that at a general election that the Conservatives would lose more than 190 English constituencies. This would give Labour a very comfortable parliamentary majority and make Sir Keir Starmer prime minister.
Because parliamentary constituencies have far more voters than councillors represent, the British election system magnifies the impact of lost local votes when they are used to forecast results in parliamentary constituencies.
April's nationwide polls asking people which party they prefer shows Labour ahead by 20 percentage points. Electoral Calculus forecasts that this would leave the Conservatives with only 85 MPs and give a Labour government an absolute House of Commons majority of 294 seats.
The polls do not give Rishi Sunak the evidence he needs to support the argument that things are starting to get better. However, a loss of "only" 400 council seats could be seized on as a straw in the wind supporting his hopes. If Conservative mayors in the West Midlands and Tees Valley win re-election this would offer more hope that the Tories can do better in an autumn general election then currently forecast .
Among the hundreds of Conservative MPs who face the prospect of losing their seats this autumn only 15 percent need to sign a no confidence motion to trigger a vote on the party leadership. In doing so they may claim they represent the views of defeated councillors and party canvassers that under Rishi Sunak the party is headed for disaster whenever a general election is held.
With current polls showing a 100 percent probability of Labour forming a government after the next election, the most a Tory recovery can hope to achieve by yet another change in leadership is a "not too disastrous" defeat. Yet there is also recent evidence suggesting that another change in leadership could lead to an "even more disastrous" defeat.
Richard Rose is Britain's senior psephologist having researched and commented on seventeen British general elections since 1959.